Cord weight pulley assemblies have heretofore been provided for use in traverse rod installations where the operating cords are arranged in a loop, to tension and maintain the operating cords in a desired position. In one prior cord weight pulley assembly, the pulley is mounted in a pulley housing that is detachably secured to a separate housing that encloses the cord weight. In another prior cord weight pulley assembly, the pulley and cord weight are disposed between two housing half-sections that snap together. However, in order to attach or remove the pulley from the cord loop, it is necessary to remove one housing half-section from the other and this not only exposes the pulley but also the cord weight. Further, if the snap fittings for connecting the housing half-section are constructed and arranged to provide a very firm interlocking of the housing half-sections, as would be desirable to retain the cord weight against accidental discharge from the housing, then the housing is difficult to open in order to install or remove the pulley from the cord loop.